This is a competitive renewal for our longstanding Training Program in Diabetes, Endocrinology, and Metabolic Diseases. During the most recent funding cycle, 4 postdoctoral fellows were supported each year, with an additional postdoctoral fellow supported through a Minority Supplement. A total of 13 trainees working with 10 different mentors were supported during this cycle. The program is designed to accommodate PhD scientists, as well as physician scientists with MD or MD/PhD degrees, of whom most enter through the Penn Clinical Fellowship Program in Endocrinology, Diabetes, and Metabolism. Of the postdoctoral trainees supported by this T32 during the last 4 years who are no longer in training, three have junior faculty positions at Penn (two with current competing offers from outside academic institutions), one is a Senior Scientist at Cellular Dynamics International, and one is an Associate Director of Clinical Research at Teva Pharmaceuticals. For the next period, we request continued funding of four postdoctoral fellows. We also request continued support of Penn's NIDDK Medical Student Research Program, which has supported 22 medical students during this funding cycle. Our 19 training faculty have primary appointments in nine Medical School Departments and one Department in the School of Veterinary Medicine and consist of 12 professors, 5 associate professors, and 2 assistant professors. Seven members of the training faculty are women and one is an underrepresented minority. In the last funding cycle, five mentors left Penn or changed status to emeritus, seven were removed, and seven were appointed to the training grant. Training grant faculty direct programs in ?-cell development and function, obesity, hormone action, physiology, diabetic complications, and genetics in humans and model organisms, with expertise in laboratory-based, translational, patient-oriented, and community-based research. This training program continues to provide superb preparation for scientists committed to careers in research into diabetes, endocrinology, and metabolism.